At the end of “Choose Your Pain,” there wasn’t a preview for the following episode of Star Trek: Discovery, and there might be a good reason why. Based on the title of the episode, we may see a character from the original series make an unexpected visit.

Speculation is ahead for Star Trek: Discovery Episode 6, “Lethe.”

The next episode of Discovery is titled “Lethe,” which could be a reference to a character of the same name who appeared in the original series episode “Dagger of the Mind.” That episode found Captain Kirk and Dr. Noel beaming down to check out a Federation rehabilitation colony on the planet Tantalus V, only to discover terrible mind experiments being performed on the inmates. And one of the former mental patients of Tantalus V was a woman named Lethe (Susanne Wasson). In the opening moments of “Dagger of the Mind,” we’re told Lethe was brought to the colony for rehab but stayed on as a therapist. The truth ends up being somewhat more twisted in the end. She’s also evasive with Captain Kirk about what she was in for.

Lethe in "Dagger of the Mind"

The Discovery episode after “Lethe” is titled “Magic to Make the Sanest Man Go Mad,” which though a reference to Homer’s The Iliad, also sounds like it’s dealing with people who have gone insane. Supposedly, Lethe was insane before she got to Tantalus V, but was she? Plus, because she never told Kirk what her crime was, could we be poised to find out what she did?

If the Lethe of “Dagger of the Mind” does, in fact, appear in the next episode of Discovery, we’ll see this Star Trek series taking its prequel status in relation to the original series even more serious than anyone thought. “Dagger of the Mind” is by no means a famous Trek episode, making the possible appearance of Lethe the deepest of deep Trek cuts on Discovery so far.


Star Trek: Discovery airs on Sundays at 8:30 p.m. Eastern on CBS All Access.

Inverse reviews Star Trek: Discovery below.